In 17 states, police keep lists of everyone who buys high-powered painkillers and other potentially addictive drugs prescribed by doctors.

They collect the information with the permission of a little-known law that requires pharmacists to send them patients' names, the drug they are taking, the name of their doctors and even the number of pills they receive.

This means that whenever you have a prescription filled for Schedule II drugs, such as Percodan, Vicodin or Lorcet — and in some states Schedule III drugs such as anabolic steroids or Ketamine, or familiar Schedule IV drugs like Xanax, Valium, or the "date rape" drug Rohypnol, plus needles and syringes — a record with your name on it is created and shared with a number of agencies.

It is all part of a computerized electronic tracking system used by the states in a federal program to help police and medical licensing agencies bust prescription drug abuses.

Schedule II drugs also include familiar painkillers such as Demerol, Percocet and the powerful OxyContin; street drugs such as cocaine and meth; and even Ritalin.

Nationally, the program is called the Prescription Drug Monitoring Program. California was the first state to implement the program, in 1940; Kentucky was the most recent to join, in 1999. Police say the program is one of the key tools used to catch drug abusers and the doctors and pharmacists who provide the drugs.

In Indiana, the program is being used in the Drug Enforcement Agency's ongoing investigation of local physicians and pharmacies suspected of providing excessive prescriptions for painkillers. Indianapolis Colts owner Jim Irsay and a handful of his associates are expected to be questioned in the investigation — even though the National Football League and Irsay's lawyer said they don't believe the team's owner is a target. Irsay has said he sought treatment for addiction to prescription painkillers.

John Krull, Indiana Civil Liberties Union executive director, said the system could put citizens' privacy at risk.

"Anytime people's privacy is violated, especially on a systemic basis, it is a concern," he said. "What if you are battling cancer and have beaten the odds and survived, but are in constant pain? Does your legitimate use of painkillers cause you to become the object of an investigation? In a free society, government should be accountable to the citizenry. More and more, the citizen is being held accountable to the government."

Les Miller, special counsel for Indiana State Police Superintendent Mel Carraway, said the monitoring program helps stop prescription drug abuse. "We need a means of tracking prescriptions for Schedule II drugs because they are subject to abuse," he said. "We could use it to build a case, to look at trends, to catch information about a doctor, a pharmacy or an individual. It is another piece of information that goes into the mix."

The information collected in the database includes:

The patient's name.

His or her date of birth.

Date the drug is dispensed.

Quantity of the drug.

Number of days supply dispensed.

Whether the prescription was phoned in or presented in writing.

The law allows public access to statistical reports only.

A Web site for the Diversion Control Program (www.deadiversion.usdoj.gov), of which the Prescription Drug Monitoring Program is a part, is packed with information about national and local cases, though names of suspected drug abusers are not included. (Investigators can track a case if needed.)

In one report on the site, DEA reported that one Indiana woman was so addicted to hydrocodone (codeine) that she had all her teeth pulled just so she could get prescriptions filled at different Indiana pharmacies.

In another case, troopers found one patient was receiving 2,500 doses of a high-powered painkiller per month from one doctor. Before the case was completed, the drug abuser was killed.